Thread-protector.



U. S. ARMSTRONQ.

THREAD PROTECTOR.

APPLICATION FILED DEC. 19. 19 14.

Patented June 6, 1916.

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v f g INVENTQR UNITED STATES PATENT OFFICE.

ULYSSES ARMSTRONG, OF lITTSBURG-H, PENNSYLVANIA.

TfiREAD-PROTEGTOR.

Specification of Letters Patent.

v Application filed December 19, 1914. Serial No. 878,174.

To all whom it may concern: p a

Be it known that I, ULYSSES S. A m- STRONG, a resident of Pittsburgh, in the county of Allegheny and State of Pennsyl-v vania, have invented a new and useful Improvement in Thread-Protectors, of which the followingis a specification- This invention relates to thread protectors,-and particularly for protecting pipe threads during the application of a coating layer of lacquer or enamel thereto.

The object of the invention is to. provide a simple device of this kind which. can be manufactured cheaply, which canbe readily applied to the pipe, which will prevent the bath of lacquer or enamel from coating the pipe threads, and which also forms an efficient.protector for preventing injury to the threads in handling the pipes and transport ing themto the place of use.

The invention comprises the thread pro-- tector hereinafter described and claimed.

In the drawings, Figure 1 represents a side elevationof a section of pipe and a coupling with thread protectors applied thereto; Fig. 2 is a perspective view on a larger scale, of" one form of thread pro tector; Fig. 3 is a similar v-iew showing the manner of assembling the same; Fig. 4 is a plan view of the protector before being bent to final form; Fig. 5-is an end view of a modified form' of protector; and Fig. 6 is i tector.

a perspective view of another form of pro- Pipes or conduits for containing electric wiring require a smooth inner surface to enable the wires to-be readily drawn through the pipes, and also an efllcient coating layer of some material which will protect the pipe from'corrosion and deterioration.

' Commonly conduits for electric wiring are made of iron or steel provided with a coating or layer of lacquer or some flexible enamel, which is appliedby dipping the pipe into a bath of the coating material and then baking the coated 'pipe in an own. such pipes are usually threaded before being coated with enamel, and if the threads are not protected in some manner the enamel coating adheres 'to and fills up the pipe threads and makes it difiicult to secure the pipes to each other or to connecting couplings, sleeves or other fittings without recutting or running the die'over the pipe or a tap through the coupling to remove the Icoating from the threads.

Patented J une 6, 1916.

To overcome the difficulties above referred I to, I apply to the threaded end of each pipe or coupling section, before placing the same in the enamel bath, a protecting device which prevents the enamel coating from adhering to the threads and leaves them uncoated,and-

which alsojis allowed to remain on the pipe after the baking operation cient protection against external injury to the threads in handling the pipes and-trans porting them to the place where used.

The protector shown in the drawings is formed of a flat metal sheet lwhich is of such gage that it can be easily bent into cylindricalform but is stiff enough" to withstand blows which the pipe might receive in handling. 'It' can be made from any suitable material, such as thin sheet/iron, steel or the like, and if desired, can be galvanized or otherwise provided with a rust-resisting coating, although this-is not essential. The width of. the sheet is equal to the, length of the threaded portion of the-pipe, while its length is something more than the pipe circumference. Said sheet is provided on two and forms an efii-' of its opposite edges with inwardly extending slits or notches 2, which can bemade by merely shearing the sheet or by removing a narrow strip therefrom. The slits 2 in the opposite side edges of the sheet are parallel with the length of the slits 2, and

the hook-shaped members 3 are interlocked with or-hooked into each other, as shown in Fig. 3, said hook-shaped members being placed on the-inside, of the cylinder, so that both thereof contact with the pipe threads when the protector is applied thereto and are therefore protected from injury.

The protector is slipped over the threaded end of the pipe, as shown in Fig. 1, and hugs the threads very closely, due to the resiliency of the metal and the loose connection of the ends of the sheet, which enables the protector to conform to the taper of the threads.

In order to protect the end edge 0f the pipe one side edge of the sheet metal protector may be crimped or bent, either before or as at 5, or may be press'ed into the body of thesheet, as indicated at 5. In applying the protector the corrugat1ons pass over the pipe threads and when it reaches its final position prevent the protector from drop ping off from the pipe.

lVhile the protector may not entlrely prevent coating of the pipe threads, it is found.

to form an etiicient protector for preventing most if not all of the enamel coating from adhering to the threads, due to the fact that an iron or steel device will not take a good coating of enamel if its surface is closely adjacent to another iron or steel member while immersed in the bath. If a number of pipes are placed in the bath fairly close to each other it is found that when baked in the oven these pipes have uncoated longitudinal streaks where they lie close to each other. This is probablydue to some coaction-between the adjacent metal surfaces, but in any case is takenadvantage of in this protector, which is found to prevent the coating from adhering to the pipe threads.

' After the pipes are baked the protectoris allowed to remain and formsan Iefiicient protection against external knocks or blows to which the pipe is subjected in handling and transporting the same. When the pipe is to be used. the protector can be readily removed by merely catching one of its free edges with a pair of pliers and tearing it loose.

The protector can also be used for internal threads on. couplings, sleeves or other fittings.

- 6 provided with an internall'y' threaded coupling 7 in which is located a protector 8. This protector is of the same construction and arrangement as that before described, except that one of its end edges is bent inwardly or toward the axisof the cylinder,

. as shown at 9, which leaves a projecting edge portion which can be readily grasped with the pliers for removing the protector-from the pipe or nipple. This protector closely hugs the threads within the pipe, due to the resiliency and expansion of the thin sheet metal,

, The internal thread protector may also be of the form shown in Fig. 6, which consists For example, Fig. 1 shows a pipe.

of a plain rectangular metal sheet 10 bent into cylindricalform and havlng one of its longitudinal edges bent inwardly, as shown at 9. This sheet is left unshttedbecause the end portions of the protector do not have with each other, said slits being substantially wider along the lengthof the sheet than the thickness of the metal.

2. A thread protect-or, comprising a thin sheet metal member having. two of its opposite edges provided with. slits extending normall to said edges and parallel to eachv other, the slitted portions of said-member being loosely interlocked whereby they can assume various positions relative to each other.

3. A thread protector, comprising a thin sheet metal member having two of its opposite side edges provided with slits extend.- ing part way across the sheet and lying parallel with each other, the slitted portions of said member being loosely interlocked to form a ring capable of accommodating itself to a tapered thread. A

4. A thread protector, comprising a thin.

sheet metal member having two of its opposite side edges provided with slits extending part way across the sheet and lying parallel with each other the slits in opposite 1 edges being adjacent opposite ends of the sheet, the slitted portions of. said member.

being loosely interlocked to form a ring ca pable of accommodating itself to a ta'pcred thread. I

5. A thread protector, comprising a thin sheet metal member having two of its opposite side edges provided with slits extending part way across the sheet and lying parallel with each other, the slits in opposite edges being adjacent opposite ends of the sheet and forming hook-shaped end members, said hook-shaped members being loosely interlocked to form a flexible ring capable of accommodating itself to a tapered'thread.

I 6. A thread protector, comprising a thin sheet metal member having twoof its opposite side edges provided with slits extending part way across the sheet and lying parallel es' with each other, the slits in opposite ed, being adjacent opposite ends of the sheet and forming hook-shaped end members,

i'io

said sheet being bent into cylindrical form and having said hook-shaped end members interlocked with each other and lying on the inside of the cylinder, said hook-shaped members being loosely interlocked to form a .fiexible ring capable 0t accommodating itself to a tapered thread.

7. A thread protector, comprising a thin, loosely interlocked With each other, one of flexible sheet metal member having hook-' the edges of said protector being bent to shaped end portions and bent into cylindriform a flange for covering the end edge of cal form With its opposite ends interlocked the pipe, said protector being adapted to 15 1 5 with each other, said member being adapted accommodate itself to a tapered thread.

to cover and conform to the pipe threads In testimony whereof, I have hereunto set and having projections for engaging with my hand.

the Same. ULYSSES s. ARMSTRONG. 8. A thread protector, comprising a thin, Witnesses: 10 flexible sheet-metal member bent to cylin- WILLIAM B..WHARToN,'

drical form and having its end portions ELBERT L. HYDE. 

